Numbers k such that k and k^2 use only the digits 0, 2, 4, 8 and 9.

Terms

a(0) =0a(1) =2a(2) =20a(3) =22a(4) =200a(5) =202a(6) =220a(7) =222a(8) =288a(9) =298a(10) =498a(11) =2000a(12) =2002a(13) =2020a(14) =2022a(15) =2200a(16) =2202a(17) =2220a(18) =2880a(19) =2980a(20) =2998a(21) =4980a(22) =4998a(23) =20000a(24) =20002a(25) =20020a(26) =20022a(27) =20200a(28) =20220a(29) =20222